Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Anode active material with whole particle concentration gradient for lithium secondary battery, method for preparing same, and lithium secondary battery having same

Active Publication Date: 2014-01-30
LG CHEM LTD
View PDF1 Cites 53 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The present invention is related to a cathode active material for a lithium secondary battery. The material has a stable crystal structure and increased thermostability due to a continuous concentration gradient of certain metals from the core to the surface part, without any rapid concentration change from the particle core to the surface part. As a result, the lithium secondary battery using this cathode active material exhibits excellent capacity, lifespan and charge / discharge characteristics, and even at high temperatures. The invention is achieved by maintaining the concentration of one metal constant from the core to the surface part and adjusting the concentrations of the other two metals with a continuous gradient from the core to the surface part.

Problems solved by technology

The P-HEV battery is a battery having characteristics, which are nearly the characteristics of an electric vehicle, and the biggest challenge is to develop high-capacity batteries.
In particular, the biggest challenge is to develop cathode materials having higher tap density of 2.0 g / cc or more and high capacity characteristics of 230 mAh / g or more.
However, because Co has low reserves and is expensive and toxic to the human body, it is needed to develop other cathode materials.
Further, it has a defect of very poor thermal properties by unstable crystal structure by delithiation during discharging.
However, there is no satisfactory result yet.
Namely, LiNi1-xCoxO2 (x=0.1-0.3) material, wherein a part of the nickel is substituted with cobalt, shows excellent charge / discharge characteristics and lifetime characteristics, but the thermostability problem is not solved yet.
However, this method has a problem that the internal structure is unstable because the metal composition of the cathode active material between the produced internal material and the external material is discontinuously changed, and is not continuously and gradually changed.
Further, the powder synthesized by the invention, which does not use ammonia as a chelating agent, was not suitable for a cathode active material for a lithium secondary battery due to its lower tap density.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Anode active material with whole particle concentration gradient for lithium secondary battery, method for preparing same, and lithium secondary battery having same
  • Anode active material with whole particle concentration gradient for lithium secondary battery, method for preparing same, and lithium secondary battery having same
  • Anode active material with whole particle concentration gradient for lithium secondary battery, method for preparing same, and lithium secondary battery having same

Examples

Experimental program
Comparison scheme
Effect test

example 1

Case of Constant Nickel Concentration

Example 1-1

[0072]In order to prepare a compound, wherein the Ni concentration is constant from the core to the surface, the Co concentration is decreased, and the Mn concentration is increased, a 2.4 M metal aqueous solution, prepared by mixing nickel sulfate and cobalt sulfate at the molar ratio of 80:20, as a metal salt aqueous solution for forming the core and a metal aqueous solution containing nickel sulfate and manganese sulfate at the molar ratio of 80:20 as a metal salt aqueous solution for forming the surface part were prepared.

[0073]Distilled water 4 L was put into a coprecipitation reactor (Capacity: 4 L, power of a rotation motor: 80 W); nitrogen gas was supplied to the reactor at the speed of 0.5 L / min so as to remove dissolved oxygen; and stirred at 1000 rpm while maintaining the temperature of the reactor at 50° C.

[0074]The metal salt aqueous solution for forming the core and the metal salt aqueous solution for forming the surface ...

example 1-2 to example 1-4

[0076]In order to prepare a compound, wherein the Ni concentration is constant from the core to the surface, the Co concentration is decreased and the Mn concentration is increased, the procedure of Example 1 was repeated except for mixing nickel sulfate, cobalt sulfate and manganese sulfate of the metal salt aqueous solution for forming the core and the metal salt aqueous solution for forming the surface part at the molar ratio as listed in the following Table 1 so as to obtain an active material particle.

example 1-5

[0077]A cathode active material, which has the same composition and the same structure with Examples 1-3 was prepared by using a batch reactor.

[0078]Distilled water 2.5 L was put into a coprecipitation batch reactor (Capacity: 8 L, power of a rotation motor: 180 W); nitrogen gas was supplied to the reactor at the speed of 0.6 L / min so as to remove dissolved oxygen; and stirred at 450 rpm while maintaining the temperature of the reactor at 50° C.

[0079]The metal salt aqueous solution for forming the core and the metal salt aqueous solution for forming the surface part having the same concentration with Example 1-3 were mixed at a certain ratio, and simultaneously supplied into the reactor at the rate of 0.2 L / hour. Further, 4.8 M ammonia solution was continuously supplied into the reactor at the rate of 0.1 L / hour. Further, for adjusting pH, 10 M NaOH aqueous solution was supplied to maintain pH in the reactor at 11. Then, the impeller speed of the reactor was controlled to 450 rpm, a...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The present invention relates to a cathode active material with whole particle concentration gradient for a lithium secondary battery, a method for preparing same, and a lithium secondary battery having same, and more specifically, to a composite cathode active material, a method for manufacturing same, and a lithium secondary battery having same, the composite cathode active material having excellent lifetime characteristics and charge / discharge characteristics through the stabilization of crystal structure as the concentration of a metal comprising the cathode active material shows concentration gradient in the whole particle, and having thermostability even in high temperatures.

Description

CROSS REFERENCE TO RELATED APPLICATION[0001]This application is a 371 of PCT / KR2011 / 010173 filed on Dec. 27, 2011, which claimed the priority of KR Patent Application No. 10-2011-0000841 filed on Jan. 5, 2011; KR Patent Application No. 10-2011-0021579 filed Mar. 10, 2011 and KR Patent Application No. 10-2011-0122542 filed Nov. 22, 2011, all applications are incorporated herein by reference in their entirety.FIELD OF THE INVENTION[0002]The present invention relates to a cathode active material with whole particle concentration gradient for a lithium secondary battery, a method for preparing same, and a lithium secondary battery having same, and more specifically, to a cathode active material with whole particle concentration gradient for a lithium secondary battery, a method for preparing same, and a lithium secondary battery having same, which has excellent lifetime characteristics and charge / discharge characteristics through the stabilization of crystal structure without rapid chan...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H01M4/36C01D15/02
CPCC01D15/02H01M4/364H01M4/483H01M4/505H01M4/525H01M10/052Y02E60/10H01M4/48H01M4/58H01M4/139Y02P70/50H01M4/131H01M4/366H01M4/502H01M4/523H01M4/54H01M10/0525H01M2004/028
Inventor SUN, YANG-KOOKNOH, HYUNG JOO
Owner LG CHEM LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com